First report of Arthroderma benhamiae in Switzerland

Changes in fungal taxonomy: mycological rationale and clinical implications

Numerous fungal species of medical importance have been recently subjected to and will likely continue to undergo nomenclatural changes as a result of the application of molecular approaches to fungal classification together with abandonment of dual nomenclature. Here, we summarize those changes affecting key groups of fungi of medical importance, explaining the mycological (taxonomic) rationale that underpinned the changes and the clinical relevance/importance (where such exists) of the key nomenclatural revisions. Potential mechanisms to mitigate unnecessary taxonomic instability are suggested, together with approaches to raise awareness of important changes to minimize potential clinical confusion.

Survey on Dermatophytes Isolated from Animals in Switzerland in the Context of the Prevention of Zoonotic Dermatophytosis

Most inflammatory dermatophytoses in humans are caused by zoophilic and geophilic dermatophytes. Knowledge of the epidemiology of these fungi in animals facilitates the prevention of dermatophytosis of animal origin in humans. We studied the prevalence of dermatophyte species in domestic animals in Switzerland and examined the effectiveness of direct mycological examination (DME) for their detection compared to mycological cultures. In total, 3515 hair and skin samples, collected between 2008 and 2022 by practicing veterinarians, were subjected to direct fluorescence microscopy and fungal culture. Overall, 611 dermatophytes were isolated, of which 547 (89.5%) were from DME-positive samples. Cats and dogs were the main reservoirs of Trichophyton mentagrophytes and Microsporum canis, whereas Trichophyton benhamiae was predominantly found in guinea pigs. Cultures with M. canis significantly (p < 0.001) outnumbered those with T. mentagrophytes in DME-negative samples (19.3% versus 6.8%), possibly because M. canis can be asymptomatic in cats and dogs, unlike T. mentagrophytes, which is always infectious. Our data confirm DME as a reliable, quick, and easy method to identify the presence of dermatophytes in animals. A positive DME in an animal hair or skin sample should alert people in contact with the animal to the risk of contracting dermatophytosis.

Fungal Flora in Asymptomatic Pet Guinea Pigs and Rabbits

Simple Summary

Small mammals hider a wide number of saprophytic fungi associated with dermatophytosis in young or immunocompromised humans. This raises the possibility of potential zoonotic transmission of dermatophytes in animals from pet shops. Therefore, it is recommended that routine fungal diagnostic testing in pet guinea pigs (Cavia porcellus) and rabbits (Oryctolagus cuniculus domesticus) be carried out, to detect potential zoonotic fungi. The almost complete lack of cutaneous lesions in many cases associated with the presence of such a dermatophyte on healthy mammals may increase the risk of zoonotic transmission. This study identifies the most common fungal species that occur on the skin in guinea pigs and rabbits and determines the rate of asymptomatic carriers in healthy pet animals.

Abstract

Fungal skin diseases are well-recognized diseases with public health implications. The study provides a comprehensive overview and aims to determine the rate of positive fungal cultures to identify the most common fungal species in guinea pigs and rabbits and to determine the rate of asymptomatic carriers in healthy pet animals. This knowledge is essential for understanding disease transmission dynamics and epidemiological situation problems. A total of 167 animals (64 rabbits and 103 guinea pigs) were investigated in this study. The fungi of the genus Penicillium, Rhizopus, Mucor, Cladosporium, and Aspergillus were the most common in the examined animals, and they were isolated from 162 (97%) of the animals enrolled. No fungal growth was observed in 5 animals. In 15 cases (8.98%), we found pathogenic zoonotic dermatophytes (Trichophyton mentagrophytes), which caused several health problems in two humans in contact with affected animals. This study presents the prevalence of fungal flora in pet guinea pigs and rabbits in Slovakia.

Alopecia and pet: a case report

Dermatophytoses are fungal infections affecting the skin and cutaneous annexes. This clinical case report describes a 7-year-old girl with Kerion celsi, a severe manifestation of Tinea capitis. The patient presented with painful edematous crusty scalp lesions and alopecia, which required surgical debridement and long-term antifungal treatment. Culture of samples collected from scalp and arm skin lesions (patient and patient’s mother respectively) were positive for Trichophyton mentagrophytes. The family owned a pet guinea pig. This particular dermatophytosis is easily transmitted from guinea pigs to humans, with some studies showing up to 34.9% prevalence of Trichophyton mentagrophytes infection in these animals.

A Polyphasic Approach to Classification and Identification of Species within the Trichophyton benhamiae Complex

In recent years, considerable advances have been made in clearing up the phylogenetic relationships within the Arthrodermataceae family. However, certain closely related taxa still contain poorly resolved species boundaries. Here, we tried to elucidate the species composition of the Trichophyton benhamiae species complex using a combined approach consisting of multi-gene phylogenetic analysis based on internal transcribed spacer (ITS) and beta-tubulin (BT) gene regions, morphological analysis, and spectral comparison using MALDI-ToF. We confirmed the existence of 11 different monophyletic clades within the complex representing either species or genetically distinct groups within species. MALDI-ToF spectrometry analysis revealed that most of these clades were readily distinguishable from one another; however, some closely related sister clades, such as T. europaeum and T. japonicum, were often misidentified as their counterpart. The distinct “yellow” and “white” phenotypes of T. benhamiae do not have a clear genetic basis and should thus be considered as different morphotypes of the same species. Strains traditionally considered T. benhamiae can be divided into three main clades: (i) T. benhamiae, (ii) T. europaeum/T. japonicum, and (iii) the phylogenetically distant T. africanum. While T. europaeum and T. japonicum are distinguishable based on their genotype, spectral and morphological analysis did not provide clear delimiting characteristics.

MFS1, a Pleiotropic Transporter in Dermatophytes That Plays a Key Role in Their Intrinsic Resistance to Chloramphenicol and Fluconazole

A recently identified Trichophyton rubrum major facilitator superfamily (MFS)-type transporter (TruMFS1) has been shown to give resistance to azole compounds and cycloheximide (CYH) when overexpressed in Saccharomyces cerevisiae. We investigated the roles of MFS1 in the intrinsic resistance of dermatophytes to CYH and chloramphenicol (CHL), which are commonly used to isolate these fungi, and to what extent MFS1 affects the susceptibility to azole antifungals. Susceptibility to antibiotics and azoles was tested in S. cerevisiae overexpressing MFS1 and ΔMFS1 mutants of Trichophyton benhamiae, a dermatophyte that is closely related to T. rubrum. We found that TruMFS1 functions as an efflux pump for CHL in addition to CYH and azoles in S. cerevisiae. In contrast, the growth of T. benhamiae ΔMFS1 mutants was not reduced in the presence of CYH but was severely impaired in the presence of CHL and thiamphenicol, a CHL analog. The suppression of MFS1 in T. benhamiae also increased the sensitivity of the fungus to fluconazole and miconazole. Our experiments revealed a key role of MFS1 in the resistance of dermatophytes to CHL and their high minimum inhibitory concentration for fluconazole. Suppression of MFS1 did not affect the sensitivity to CYH, suggesting that another mechanism was involved in resistance to CYH in dermatophytes.

Familial Cases of Trichophyton benhamiae Infection Transmitted from a Guinea Pig in Iran

Trichophyton benhamiae is a zoophilic dermatophyte mainly transmitted to humans from guinea pigs. This zoophilic species can also cause dermatophytosis as reported by human contact with other animals, such as rabbit, cat, and fox. Here, we report the tinea faciei and tinea corporis cases: a 12-year-old girl and her 53-year-old father, with no history of immunodeficiency and underlying disease, caused by T. benhamiae transmitted from a guinea pig in Iran. Dermatological examination revealed several erythematous, round, scaly, and approximately 1-4-cm-diameter lesions in both patients. The girl had seven skin lesions, and her father presented two skin lesions on the front side of his neck. The girl's lesions had started 3 weeks before and her father's lesions appeared 7 days after the first clinical appearance of the lesions in the daughter. The girl had daily close contact with a guinea pig, while her father did not have any direct exposure to the pet. Examination of the lesions scraping with 10% potassium hydroxide (KOH 10%) revealed hyaline septate hyphae and arthroconidia. The dermatophyte isolated in culture was identified as T. benhamiae using molecular analysis. The patients were successfully treated using topical sertaconazole nitrate 2% cream twice a day for 4 weeks.

Investigation of in vitro antifungal susceptibility testing and genetic diversity of clinical isolates of Trichophyton benhamiae and Trichophyton eriotrephon in Iran

BACKGROUND

Trichophyton benhamiae is a zoophilic dermatophyte, known as one of the causative agents of dermatophytosis.

OBJECTIVES

The purpose of this study was to explore the genotypes of T. benhamiae strains isolated from geographically different areas of Iran and also to evaluate in vitro antifungal susceptibility profile of these strains against seven antifungal drugs.

METHODS

Twenty-two strains of T. benhamiae and two strains of T. eriotrephon were isolated from patients with distinct types of dermatophytosis. DNA extraction and amplification of rDNA regions using ITS1 and ITS4 primers were conducted on the isolates. The in vitro antifungal susceptibility of posaconazole (PSC), voriconazole (VRC), itraconazole (ITC), ketoconazole (KET), caspofungin (CAS), terbinafine (TRB) and griseofulvin (GRZ) was evaluated according to CLSI M38-A2 protocol.

RESULTS

The multiple alignment of the ITS-rDNA sequences of T. benhamiae indicated a mean similarity of 99.5%, with 0-3 interspecies nucleotide difference. The geometric mean (GM) values of minimum inhibitory concentrations (MICs) and minimum effective concentrations (MECs) across the all isolates were respectively: TRB: 0.025 mg/L, PSC: 0.032 mg/L, ITC: 0.050 mg/L and VRC: 0.059 mg/L with lower values and CAS: 0.31 mg/L, KTZ: 0.56 mg/L and GRZ: 0.76 mg/L with higher values.

CONCLUSION

Diverse ITS sequence types of T. benhamiae were shown in different geographical regions of Iran. The TRB, PSC and ITC were the most effective drugs against T. benhamiae strains, respectively. Furthermore, in our study, two strains of T. eriotrephon as a scarce dermatophyte species were described.

Epidemiology of Dermatophytoses in Switzerland According to a Survey of Dermatophytes Isolated in Lausanne between 2001 and 2018

Dermatophytes are the most common pathogenic agents of superficial mycoses in humans and animals. Knowledge of their epidemiology can facilitate the prevention of dermatophytosis and improve prophylactic measures. We sought to determine the incidence of the different dermatophyte species diagnosed in Lausanne (Switzerland) from 2001 to 2018. In total, 10,958 dermatophytes were isolated from patients and 459 from pets. Overall, 99% of tinea unguium and tinea pedis were caused by Trichophyton rubrum and Trichophyton interdigitale with a prevalence ratio of 3:1. Trichophyton violaceum and Trichophyton soudanense were mainly found in tinea capitis in patients of African and Mediterranean origin. Interestingly, while Epidermophyton floccosum and Trichophyton verrucosum were prevalent 50 years ago in an epidemiological analysis carried out in the same laboratory from 1967 to 1970, these two species were rarely detected from 2001 to 2018. Trichophyton mentagrophytes, Trichophyton benhamiae and Microsporum canis were the prevalent zoophilic pathogenic species in children and young adults. Our investigation of animal samples revealed the main reservoirs of these zoophilic species to be cats and dogs for T. mentagrophytes and M. canis, and Guinea pigs for T. benhamiae. This study provides an epidemiological overview of dermatophytoses in Switzerland to improve their surveillance.

A case of Tinea Faciei caused by Trichophyton benhamiae: first report in China

Background

Trichophyton benhamiae is a zoophilic dermatophyte that can cause tinea in humans and animals. Lesions caused by T. benhamiae tend to be highly inflammatory, and patients are often infected by animals or other patients infected with T. benhamiae. In this paper, we report the first case of tinea faciei caused by T. benhamiae in a Chinese girl who might be transmitted from a fox.

Case presentation

A 4-year-old girl from HaiNing city developed an itchy, erythematous, and annular plaque on her right face for the past 2 months. Before the lesion appeared, she was in close contact with the fur of a fox for almost 1 week. Septate hyaline hyphae were detected by direct mycological examination of the scales. Cultures grew on Sabouraud’s dextrose agar (SDA) at 26 °C for 2 weeks revealed the presence of T. mentagrophytes. A molecular sequencing test confirmed that the isolate was consistent with reference strains to T. benhamiae. Then, the diagnosis of tinea faciei due to T. benhamiae was made. Treatment with terbinafine (oral 125 mg/d) and sertaconazole nitrate cream (topical, twice daily) for 4 weeks was initiated and achieved significant improvement of the skin lesions.

Conclusions

This rare dermatophytosis case highlights the importance of ITS sequencing in helping to recognize rare pathogenic fungi that can be easily misdiagnosed with a conventional morphological diagnosis.

Mating analyses of Trichophyton benhamiae offspring reveals linkage of genetic markers used in taxonomy

Mating experiments were conducted with four clinical Trichophyton benhamiae isolates, genetically similar to the Trichophyton benhamiae CBS 112371, featuring the plus mating type and with two minus type strains. One minus type strain belonged to the white subgroup, and the other minus type strain, DSM 6916, showed genetic kinship to the yellow subgroup. Only two plus type strains were able to form mature, pigmented gymnothecia with DSM 6916. These two plus type strains demonstrated dark pigmentation and powdery mycelium on Takashio agar, whereas the other three strains exhibited a low degree of pigmentation on the same medium. All five plus strains were able to mate with the minus type strain of their own white subgroup. Cultures from single ascospore isolates showed highly variable morphology and pigmentation. Three genetic markers (ITS, mating type, EF1 alpha) were analyzed in polymerase chain reaction (PCR) experiments with optimized primers and PCR conditions to discriminate between subgroups. Furthermore, RAPD-PCR was used to generate a DSM 6916-specific DNA-fragment which served as an additional genetic marker. Assessing the isolates with recombinant genotypes, it was found that three genetic markers behave like linked genes. The recombination of plus mating type went together with ITS, EF1 alpha and RAPD marker of the DSM 6916 parental strain and was most frequently isolated, whereas plus types recombinants in this case were completely missing. This shows a high imbalance in mating type distribution of recombinants.

Would you like to purchase a rodent with dermatophytes?

The zoophilic dermatophyte Trichophyton benhamiae has received attention due to increasing infections in human in recent years. Trichophyton benhamiae has been found on asymptomatic rodents from pet shops in several countries posing a potential risk for transmission to humans. The aim of this study was to determine the prevalence of positive dermatophyte cultures from rodents in Danish pet shops in order to clarify the magnitude of potential sources of zoophilic infections and to prevent further spread. Specimen sampling was performed in 17 Danish pet shops using the brush technique (MacKenzie technique). After incubation, cultures were sent to ITS DNA sequencing for molecular species identification. Pet shop employees were asked to fulfil a five-question survey regarding purchase and procedures of diseased animals. A total of 98 animals were sampled (N = 32 rabbits, N = 32 guinea pigs and N = 34 hamsters). Trichophyton benhamiae was found in 14/98 samples (14%); 12/32 guinea pigs (38%) were positive with T benhamiae, 2/34 (6%) hamsters and 0/32 rabbits (0%). We found that hamsters and particularly guinea pigs from Danish pet shops are common asymptomatic carriers of the dermatophyte T benhamiae. Although a larger study is warranted to test this postulate, and it raises the question if infection control measures should be implemented in pet shops.

Prevalence and zoonotic risks of Trichophyton mentagrophytes and Cheyletiella spp. in guinea pigs and rabbits in Dutch pet shops

Young rabbits and guinea pigs are often purchased as pets for children and may be infected with zoonotic skin infections. To assess the risk of acquiring such an infection from rabbits or guinea pigs, this study investigated the prevalence of the fungus Trichophyton mentagrophytes and the fur mite Cheyletiella parasitovorax in asymptomatic rabbits and guinea pigs in Dutch pet shops. In 91 pet shops a total of 213 rabbits and 179 guinea pigs were sampled using the Mackenzie technique and cultured. Clean cultures were examined microscopically and a PCR was performed on at least one sample from each pet shop. All animals were investigated for fur mite using a flea comb, a magnifying glass and white paper. From the fur of 3.8% (8/213) of the rabbits and 16.8% (30/179) of the guinea pigs, T. mentagrophytes was isolated. From 1 guinea pig (0,6%) Chrysosporium keratinophilum was isolated. Dermatophyte-positive rabbits and guinea pigs originated from 5.6% (5/90) and 27.3% (24/88) of the investigated pet shops, respectively. Fur mites were not found. Pet shops can play an important role in preventing transmission of zoonotic ringworm infections (dermatophytosis) and educating their customers. Specific preventive measures such as routine screening examinations and (prophylactic) treatment of rabbits and guinea pigs are recommended next to regular hygiene when handling animals.

[Microsporum canis: Current data on the prevalence of the zoophilic dermatophyte in central Germany]

BACKGROUND

Microsporum (M.) canis, whose source of infection is mostly cats, is still considered as the most frequently occurring zoophilic dermatophyte in Germany and Europe. In distinct areas of Germany, the zoophilic dermatophyte Trichophyton (T.) anamorph of Arthroderma (A.) benhamiae also presents a frequent and emerging causative agent of dermatophytoses.

MATERIALS AND METHODS

Over a period of 3 years, from March 2010 to March 2013, skin samples from scalp, face, trunk, and limbs were investigated using mycological cultivation and by polymerase chain reaction (PCR) for dermatophytes. Materials originated in particular from the German Free States Saxony and Thuringia, and from the Federal State Saxony-Anhalt, but also included samples submitted from around Germany. The cultural detection of dermatophytes was performed on Sabouraud's 4% glucose agar with and without cycloheximide. For dermatophyte DNA detection, a uniplex PCR-ELISA was used.

RESULTS

In all, 8464 samples from a total of 7680 patients were investigated. In 114 (1.5%) of 7680 patients, M. canis could be detected both by culture and/or PCR. M. canis was detected culturally in 100 samples, in 107 samples by PCR, in 91 samples both culturally and by PCR. For 12 patients, only cultural detection was done (without PCR). Also detected was tinea corporis due to M. canis in 59 patients, tinea capitis 8, tinea faciei 5, and tinea manus 2 patients. Of the patients, 45% were younger than 20 years, 42% were 20-49 years old, and 13% were 50 years or older. In comparison, T. anamorph of A. benhamiae was detectable by culture and/or PCR in 231 of 7680 patients (2.9%). M. canis was the second most common zoophilic dermatophyte.

CONCLUSIONS

M. canis is still a frequent zoophilic dermatophyte in Germany. Since a few years ago, a rise of infections due to T. anamorph of A. benhamiae has been observed in Germany and other European countries. At least in distinct regions of Germany, this zoophilic dermatophyte, which is transferred from guinea pigs to human beings, currently seems to be more frequent when compared to M. canis.

Trichophyton erinacei in pet hedgehogs in Spain: Occurrence and revision of its taxonomic status

Hedgehogs have increased in popularity as pets in Spain but there are no data of infection rates of this exotic animal with dermatophytes in our country. During the period of 2008-2011 a total of 20 pet hedgehogs (19 African pygmy hedgehogs and 1 Egyptian long-eared hedgehog) suspected of having dermatophytoses were studied. This is the first survey of the occurrence of T. erinacei in household hedgehogs in Spain. The T. erinacei infection rate was 50% (9 out of 19 African pygmy hedgehogs, and the one Egyptian long-eared hedgehog surveyed). Morphological identification of the isolates was confirmed by molecular analysis. All the strains had the same ITS sequence and showed 100% sequence similarity to T. erinacei type strain CBS 511.73 (AB 105793). The Spanish isolates were confirmed as T. erinacei urease positive. On the basis of ITS sequences, T. erinacei is a species close to but separate from the taxa included in the A. benhamiae complex. Review of the current literature on DNA-based methods for identification of species included in this complex has highlighted the urgent need to reach a consensus in species circumscription and classification system accepted by all mycologists.

RNA Sequencing-Based Genome Reannotation of the Dermatophyte Arthroderma benhamiae and Characterization of Its Secretome and Whole Gene Expression Profile during Infection

Dermatophytoses (ringworm, jock itch, athlete’s foot, and nail infections) are the most common fungal infections, but their virulence mechanisms are poorly understood. Combining transcriptomic data obtained from growth under various culture conditions with data obtained during infection led to a significantly improved genome annotation. About 65% of the protein-encoding genes predicted with our protocol did not match the existing annotation for A. benhamiae. Comparing gene expression during infection on guinea pigs with keratin degradation in vitro, which is supposed to mimic the host environment, revealed the critical importance of using real in vivo conditions for investigating virulence mechanisms. The analysis of genes expressed in vivo, encoding cell surface and secreted proteins, particularly proteases, led to the identification of new allergen and virulence factor candidates.

Dermatophytes are the most common agents of superficial mycoses in humans and animals. The aim of the present investigation was to systematically identify the extracellular, possibly secreted, proteins that are putative virulence factors and antigenic molecules of dermatophytes. A complete gene expression profile of Arthroderma benhamiae was obtained during infection of its natural host (guinea pig) using RNA sequencing (RNA-seq) technology. This profile was completed with those of the fungus cultivated in vitro in two media containing either keratin or soy meal protein as the sole source of nitrogen and in Sabouraud medium. More than 60% of transcripts deduced from RNA-seq data differ from those previously deposited for A. benhamiae. Using these RNA-seq data along with an automatic gene annotation procedure, followed by manual curation, we produced a new annotation of the A. benhamiae genome. This annotation comprised 7,405 coding sequences (CDSs), among which only 2,662 were identical to the currently available annotation, 383 were newly identified, and 15 secreted proteins were manually corrected. The expression profile of genes encoding proteins with a signal peptide in infected guinea pigs was found to be very different from that during in vitro growth when using keratin as the substrate. Especially, the sets of the 12 most highly expressed genes encoding proteases with a signal sequence had only the putative vacuolar aspartic protease gene PEP2 in common, during infection and in keratin medium. The most upregulated gene encoding a secreted protease during infection was that encoding subtilisin SUB6, which is a known major allergen in the related dermatophyte Trichophyton rubrum.

IMPORTANCE Dermatophytoses (ringworm, jock itch, athlete’s foot, and nail infections) are the most common fungal infections, but their virulence mechanisms are poorly understood. Combining transcriptomic data obtained from growth under various culture conditions with data obtained during infection led to a significantly improved genome annotation. About 65% of the protein-encoding genes predicted with our protocol did not match the existing annotation for A. benhamiae. Comparing gene expression during infection on guinea pigs with keratin degradation in vitro, which is supposed to mimic the host environment, revealed the critical importance of using real in vivo conditions for investigating virulence mechanisms. The analysis of genes expressed in vivo, encoding cell surface and secreted proteins, particularly proteases, led to the identification of new allergen and virulence factor candidates.

The transcriptional regulators SteA and StuA contribute to keratin degradation and sexual reproduction of the dermatophyte Arthroderma benhamiae

Most superficial fungal infections are caused by dermatophytes, a specialized group of filamentous fungi which exclusively infect keratinized host structures such as hair, skin and nails. Since little is known about the molecular basis of pathogenicity and sexual reproduction in dermatophytes, here we functionally addressed two central transcriptional regulators, SteA and StuA. In the zoophilic species Arthroderma benhamiae a strategy for targeted genetic manipulation was recently established, and moreover, the species is teleomorphic and thus allows performing assays based on mating. By comparative genome analysis homologs of the developmental regulators SteA and StuA were identified in A. benhamiae. Knock-out mutants of the corresponding genes as well as complemented strains were generated and phenotypically characterized. In contrast to A. benhamiae wild type and complemented strains, both mutants failed to produce sexual reproductive structures in mating experiments. Analysis of growth on keratin substrates indicated that loss of steA resulted in the inability of ΔsteA mutants to produce hair perforation organs, but did not affect mycelia formation during growth on hair and nails. By contrast, ΔstuA mutants displayed a severe growth defect on these substrates, but were still able to produce hair perforations. Hence, formation of hair perforation organs and fungal growth on hair per se are differentially regulated processes. Our findings on the major role of SteA and StuA during sexual development and keratin degradation in A. benhamiae provide insights into their role in dermatophytes and further enhance our knowledge of basic biology and pathogenicity of these fungi.

HapX Mediates Iron Homeostasis in the Pathogenic Dermatophyte Arthroderma benhamiae but Is Dispensable for Virulence

For many pathogenic fungi, siderophore-mediated iron acquisition is essential for virulence. The process of siderophore production and further mechanisms to adapt to iron limitation are strictly controlled in fungi to maintain iron homeostasis. Here we demonstrate that the human pathogenic dermatophyte Arthroderma benhamiae produces the hydroxamate siderophores ferricrocin and ferrichrome C. Additionally, we show that the iron regulator HapX is crucial for the adaptation to iron starvation and iron excess, but is dispensable for virulence of A. benhamiae. Deletion of hapX caused downregulation of siderophore biosynthesis genes leading to a decreased production of siderophores during iron starvation. Furthermore, HapX was required for transcriptional repression of genes involved in iron-dependent pathways during iron-depleted conditions. Additionally, the ΔhapX mutant of A. benhamiae was sensitive to high-iron concentrations indicating that HapX also contributes to iron detoxification. In contrast to other pathogenic fungi, HapX of A. benhamiae was redundant for virulence and a ΔhapX mutant was still able to infect keratinized host tissues in vitro. Our findings underline the highly conserved role of the transcription factor HapX for maintaining iron homeostasis in ascomycetous fungi but, unlike in many other human and plant pathogenic fungi, HapX of A. benhamiae is not a virulence determinant.

Trichophyton species of Arthroderma benhamiae - a new infectious agent in dermatology

In Germany, infections due to the zoophilic dermatophyte Trichophyton (T.) species of Arthroderma benhamiae are being more frequently diagnosed. The source of infection of this emerging pathogen overlaps with that of the zoophilic species T. interdigitale. The most common source are guinea pigs. T. species of Arthroderma benhamiae causes inflammatory dermatophytosis in children and adolescents. In addition to tinea capitis, it may cause both tinea corporis, tinea manus and frequently tinea faciei. In Germany, T. species of Arthroderma benhamiae is a frequent zoophilic dermatophyte, which in regions is probably more frequent than Microsporum canis. The mycological identification of the isolates with their yellow stained colonies is based on their macroscopic and microscopic features. However, some exhibit colony features consistent with those of T. interdigitale. These strains only can be identified unambiguously by means of molecular techniques. Using detection methods such as PCR-ELISA or real-time PCR, the dermatophyte can be identified directly from clinical material. Sequencing of the internal transcribed spacer region (ITS) of the ribosomal DNA has been approved as culture confirmation test for T. species of Arthroderma benhamiae. In addition, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) is useful. Widespread dermatophytosis due to T. species of Arthroderma benhamiae, in particular of tinea capitis, requires oral antifungal agents. Terbinafine is most effective, alternatives are fluconazole and itraconazole.

Which Fungus Originally was Trichophyton mentagrophytes? Historical Review and Illustration by a Clinical Case

Several dermatophytes producing numerous pyriform or round microconidia were called Trichophyton mentagrophytes. Among these dermatophytes are the teleomorph species Arthroderma benhamiae, Arthroderma vanbreuseghemii and Arthroderma simii, and other species such as Trichophyton interdigitale, Trichophyton erinacei and Trichophyton quinckeanum for which only the anamorph is known. Confusion exists about which fungus should be really called T. mentagrophytes and about the rational use of this name in practice. We report a case of beard ringworm (tinea barbae) with A. vanbreuseghemii. According to both clinical signs and the type of hair parasitism, this case was exactly compatible to the first description of a non-favic dermatophytosis by Gruby under the name of "mentagrophyte" from which was derived the dermatophyte epithet mentagrophytes. In addition, the phenotypic characters of the isolated fungus in cultures perfectly matched with those of the first description of a dermatophyte under T. mentagrophytes by Blanchard (Parasites animaux et parasites végétaux à l'exclusion des Bactéries, Masson, Paris, 1896). In conclusion, T. mentagrophytes corresponds to the fungus later named A. vanbreuseghemii. However, because the neotype of T. mentagrophytes was not adequately designated in regard to the ancient literature, we would privilege the use of A. vanbreuseghemii and abandon the name of T. mentagrophytes.

An outbreak of Arthroderma vanbreuseghemii dermatophytosis at a veterinary school associated with an infected horse

We report a case of an outbreak of inflammatory dermatophytoses caused by Arthroderma vanbreuseghemii (formally Trichophyton mentagrophytes pro parte) that involved an infected horse, the owner and at least 20 students, staff and stablemen at a veterinary school in Bern (Switzerland) that presented highly inflammatory dermatitis of the body and the face. Transmission from human to human was also recorded as one patient was the partner of an infected person. Both the phenotypic characteristics and ITS sequence of the dermatophytes isolated from the horse and patients were identical, consistent with the conclusion that the fungus originated from the horse. Three infected persons had not been in direct contact with the horse. Although direct transmission from human to human cannot be ruled out, fomites were most likely the source of infection for these three patients. Inspection of the literature at the end of the nineteenth and beginning of the twentieth century revealed that this dermatophyte was frequently transmitted from horses to humans in contact with horses (stablemen, coachmen, carters and artillery soldiers). The rarity of the present case report at the present time is likely related to the transformation of civilisation from the nineteenth century to nowadays in Europe with the change of horse husbandry. In addition, the inadequate immune response of the horse and the high number of people in contact with it at the equine clinic may explain the exceptional aspect of this case report.

Molecular identification and classification of Trichophyton mentagrophytes complex strains isolated from humans and selected animal species

Species differentiation within Trichophyton mentagrophytes complex group currently poses a major diagnostic challenge, with molecular methods increasingly supplementing classical identification based on the morphological and physiological properties of the fungi. Diagnostic and epidemiological research aimed at determining the source and means of transmission of dermatophytoses in both humans and animals requires not only species differentiation of isolates but also differentiation within species. The study was conducted on 24 isolates originating in humans and various animal species with clinical symptoms of dermatophytosis. The analysis included phenotypical identification methods and molecular methods: internal transcribed spacer sequencing and ITS-restriction fragment length polymorphism (RFLP) with multi-enzyme restriction. ITS sequence analysis identified the isolates to species - Trichophyton interdigitale, Arthroderma benhamiae and A. vanbreuseghemii, and ITS-RFLP detected six different genotypes. Genotypes I, II and III characterised strains belonging to A. benhamiae, genotype IV characterised the A. vanbreuseghemii strain, and genotypes V and VI occurred only within the species T. interdigitale. Strains isolated from guinea pigs were dominant within genotype I, while genotype II was found mainly in strains from foxes. Multi-enzyme restriction analysis of this region enables intraspecific differentiation, which may be useful in epidemiological research, particularly in determining the source of infections.

Assessment of the cutaneous immune response during Arthroderma benhamiae and A. vanbreuseghemii infection using an experimental mouse model

BACKGROUND

Dermatophytoses are common but poorly understood skin infections. Most in vivo studies have been performed using the guinea pig as the experimental animal model, which has several limitations.

OBJECTIVES

To develop a mouse model of dermatophytosis suitable for multiple purposes, including the investigation of immunity against dermatophytes.

MATERIALS AND METHODS

Two peculiar fungal species, Arthroderma benhamiae and A. vanbreuseghemii, isolated from tinea in humans having contact with rodents were used for epicutaneous inoculation. During the infection, clinical and histopathological follow-up were performed. The recruitment of immune cells was evaluated by immunofluorescence staining and the levels of cytokine mRNA were quantified by quantitative reverse transcriptase-polymerase chain reaction in the skin of infected mice.

RESULTS

The skin symptoms and microscopic lesions, including the colonization of keratinized epidermal and follicular structures by both dermatophytes, were highly similar to those observed in guinea pig infection models and in natural infections, mimicking acute superficial tinea in humans. The dermal inflammatory cellular infiltrate consisted of macrophages, dendritic cells and especially polymorphonuclear neutrophils, which are one of the histological 'clues' to the diagnosis of dermatophytosis. The in situ cytokine profile was characterized by the overexpression of transforming growth factor-β, interleukin (IL)-1β and IL-6 mRNA during infection, suggesting a role of the T-helper 17 pathway in the establishment of immunity.

CONCLUSIONS

Our new reproducible and validated mouse model of dermatophytosis is a modern in vivo tool that allows a more in-depth understanding of the pathogenesis of human dermatophyte infections.

Development of an enzyme-linked immunosorbent assay for serodiagnosis of ringworm infection in cattle

The aim of this study was to develop an in-house enzyme-linked immunosorbent assay (ELISA) for the serological diagnosis of ringworm infection in cattle. We used available recombinant forms of Trichophyton rubrum dipeptidyl peptidase V (TruDppV) and T. rubrum leucin aminopeptidase 2 (TruLap2), which are 98% identical to Trichophyton verrucosum orthologues. Field serum samples from 135 cattle with ringworm infection, as confirmed by direct microscopy, fluorescence microscopy, and PCR, and from 55 cattle without any apparent skin lesions or history of ringworm infection that served as negative controls were used. Sensitivities, specificities, and positive and negative predictive values were determined to evaluate the diagnostic value of our ELISA. Overall, the ELISAs based on recombinant TruDppV and TruLap2 discriminated well between infected animals and healthy controls. Highly significant differences (P < 0.0001, Mann-Whitney U test) were noted between optical density values obtained when sera from infected versus control cattle were tested. The ELISA developed for the detection of specific antibodies against DppV gave 89.6% sensitivity, 92.7% specificity, a 96.8% positive predictive value, and a 78.4% negative predictive value. The recombinant TruLap2-based ELISA displayed 88.1% sensitivity, 90.9% specificity, a 95.9% positive predictive value, and a 75.7% negative predictive value. To the best of our knowledge, this is the first ELISA based on recombinant antigens for assessing immune responses to ringworm infection in cattle; it is particularly suitable for epidemiological studies and also for the evaluation of vaccines and/or vaccination procedures.

Keratin degradation by dermatophytes relies on cysteine dioxygenase and a sulfite efflux pump

Millions of people suffer from superficial infections caused by dermatophytes. Intriguingly, these filamentous fungi exclusively infect keratin-rich host structures such as hair, nails, and skin. Keratin is a hard, compact protein, and its utilization by dermatophytes for growth has long been discussed as a major virulence attribute. Here, we provide strong support for the hypothesis that keratin degradation is facilitated by the secretion of the reducing agent sulfite, which can cleave keratin-stabilizing cystine bonds. We discovered that sulfite is produced by dermatophytes from environmental cysteine, which at elevated concentrations is toxic for microbes and humans. We found that sulfite formation from cysteine relies on the key enzyme cysteine dioxygenase Cdo1. Sulfite secretion is supported by the sulfite efflux pump Ssu1. Targeted mutagenesis proved that dermatophyte mutants in either Cdo1 or Ssu1 were highly growth-sensitive to cysteine, and mutants in Ssu1 were specifically sensitive to sulfite. Most notably, dermatophyte mutants in Cdo1 and Ssu1 were specifically growth-defective on hair and nails. As keratin is rich in cysteine, our identified mechanism of cysteine conversion and sulfite efflux supports both cysteine and sulfite tolerance per se and progression of keratin degradation. These in vitro findings have implications for dermatophyte infection pathogenesis.

A simple and rapid method to differentiate Arthroderma benhamiae from Microsporum canis

BACKGROUND

Arthroderma benhamiae is increasingly isolated in Central Europe. In culture, this dermatophyte is difficult to differentiate macroscopically from Microsporum canis, which is microscopically also true for weak or non-sporulating strains. Although there are valid molecular methods for differentiating between these two dermatophytes, in everyday practice it would be helpful for epidemiological and treatment considerations to have a simple and rapid method available for discrimination.

METHODS

Five commercially available chromogenic agar media were incubated with culture material of M. canis and A. benhamiae of different ages (2-21 days). Their color was evaluated at different temperatures (4, 20, 25, and 30 ∞C) and for different incubation periods (2 hours - 7 days).

RESULTS

Under the selected conditions, Candi-Select(TM) 4 was most suitable. All M. canis strains tested (n = 21) showed a pink or purple coloration of the agar, while 5 out of 6 A. benhamiae strains (n = 30) showed a turquoise coloration. The best results were achieved with an incubation temperature of 25 ∞C and small inocula derived from primary cultures. Results could be evaluated after 2-4 hours.

CONCLUSIONS

In addition to searching for the origin of infection (in A. benhamiae almost exclusively guinea pigs, and for M. canis dogs and cats), distinguishing between the Trichophyton and Microsporum genera is most important, especially for the selection of a systemic antimycotic agent in the treatment of tinea capitis in children. In the case of M. canis terbinafine is not the first choice, but rather griseofulvin, fluconazole or itraconazole. We present a method of differentiation using Candi-Select(TM) 4. When done with a primary culture, this allows for presumptive identification within a few hours and thus prompt initiation of pathogen-specific therapy.

The Arthroderma benhamiae hydrophobin HypA mediates hydrophobicity and influences recognition by human immune effector cells

Dermatophytes are the most common cause of superficial mycoses in humans and animals. They can coexist with their hosts for many years without causing significant symptoms but also cause highly inflammatory diseases. To identify mechanisms involved in the modulation of the host response during infection caused by the zoophilic dermatophyte Arthroderma benhamiae, cell wall-associated surface proteins were studied. By two-dimensional gel electrophoresis, we found that a hydrophobin protein designated HypA was the dominant cell surface protein. HypA was also detected in the supernatant during the growth and conidiation of the fungus. The A. benhamiae genome harbors only a single hydrophobin gene, designated hypA. A hypA deletion mutant was generated, as was a complemented hypA mutant strain (hypA(C)). In contrast to the wild type and the complemented strain, the hypA deletion mutant exhibited "easily wettable" mycelia and conidia, indicating the loss of surface hydrophobicity of both morphotypes. Compared with the wild type, the hypA deletion mutant triggered an increased activation of human neutrophil granulocytes and dendritic cells, characterized by an increased release of the immune mediators interleukin-6 (IL-6), IL-8, IL-10, and tumor necrosis factor alpha (TNF-α). For the first time, we observed the formation of neutrophil extracellular traps against dermatophytes, whose level of formation was increased by the ΔhypA mutant compared with the wild type. Furthermore, conidia of the ΔhypA strain were killed more effectively by neutrophils. Our data suggest that the recognition of A. benhamiae by the cellular immune defense system is notably influenced by the presence of the surface rodlet layer formed by the hydrophobin HypA.

Genome mining reveals the presence of a conserved gene cluster for the biosynthesis of ergot alkaloid precursors in the fungal family Arthrodermataceae

Genome sequence analysis of different fungi of the family Arthrodermataceae revealed the presence of a gene cluster consisting of five genes with high sequence similarity to those involved in the early common steps of ergot alkaloid biosynthesis in Aspergillus fumigatus and Claviceps purpurea. To provide evidence that this cluster is involved in ergot alkaloid biosynthesis, the gene ARB_04646 of the fungus Arthroderma benhamiae was cloned into pQE60 and expressed in Escherichia coli. Enzyme assays with the soluble tetrameric His(6)-tagged protein proved unequivocally that the deduced gene product, here termed ChaDH, catalysed the oxidation of chanoclavine-I in the presence of NAD(+), resulting in the formation of chanoclavine-I aldehyde. The enzyme product was unequivocally proven by NMR and MS analyses. Therefore, ChaDH functions as a chanoclavine-I dehydrogenase. K(m) values for chanoclavine-I and NAD(+) were 0.09 and 0.36 mM, respectively. Turnover number was 0.76 s(-1).

Identification of novel secreted proteases during extracellular proteolysis by dermatophytes at acidic pH

The dermatophytes are a group of closely related fungi which are responsible for the great majority of superficial mycoses in humans and animals. Among various potential virulence factors, their secreted proteolytic activity attracts a lot of attention. Most dermatophyte-secreted proteases which have so far been isolated in vitro are neutral or alkaline enzymes. However, inspection of the recently decoded dermatophyte genomes revealed many other hypothetical secreted proteases, in particular acidic proteases similar to those characterized in Aspergillus spp. The validation of such genome predictions instigated the present study on two dermatophyte species, Microsporum canis and Arthroderma benhamiae. Both fungi were found to grow well in a protein medium at acidic pH, accompanied by extracellular proteolysis. Shotgun MS analysis of secreted protein revealed fundamentally different protease profiles during fungal growth in acidic versus neutral pH conditions. Most notably, novel dermatophyte-secreted proteases were identified at acidic pH such as pepsins, sedolisins and acidic carboxypeptidases. Therefore, our results not only support genome predictions, but demonstrate for the first time the secretion of acidic proteases by dermatophytes. Our findings also suggest the existence of different pathways of protein degradation into amino acids and short peptides in these highly specialized pathogenic fungi.

Targeted gene deletion and in vivo analysis of putative virulence gene function in the pathogenic dermatophyte Arthroderma benhamiae

Dermatophytes cause the majority of superficial mycoses in humans and animals. However, little is known about the pathogenicity of this specialized group of filamentous fungi, for which molecular research has been limited thus far. During experimental infection of guinea pigs by the human pathogenic dermatophyte Arthroderma benhamiae, we recently detected the activation of the fungal gene encoding malate synthase AcuE, a key enzyme of the glyoxylate cycle. By the establishment of the first genetic system for A. benhamiae, specific ΔacuE mutants were constructed in a wild-type strain and, in addition, in a derivative in which we inactivated the nonhomologous end-joining pathway by deletion of the A. benhamiae KU70 gene. The absence of AbenKU70 resulted in an increased frequency of the targeted insertion of linear DNA by homologous recombination, without notably altering the monitored in vitro growth abilities of the fungus or its virulence in a guinea pig infection model. Phenotypic analyses of ΔacuE mutants and complemented strains depicted that malate synthase is required for the growth of A. benhamiae on lipids, major constituents of the skin. However, mutant analysis did not reveal a pathogenic role of the A. benhamiae enzyme in guinea pig dermatophytosis or during epidermal invasion of the fungus in an in vitro model of reconstituted human epidermis. The presented efficient system for targeted genetic manipulation in A. benhamiae, paired with the analyzed infection models, will advance the functional characterization of putative virulence determinants in medically important dermatophytes.

Comparative and functional genomics provide insights into the pathogenicity of dermatophytic fungi

BACKGROUND

Millions of humans and animals suffer from superficial infections caused by a group of highly specialized filamentous fungi, the dermatophytes, which exclusively infect keratinized host structures. To provide broad insights into the molecular basis of the pathogenicity-associated traits, we report the first genome sequences of two closely phylogenetically related dermatophytes, Arthroderma benhamiae and Trichophyton verrucosum, both of which induce highly inflammatory infections in humans.

RESULTS

97% of the 22.5 megabase genome sequences of A. benhamiae and T. verrucosum are unambiguously alignable and collinear. To unravel dermatophyte-specific virulence-associated traits, we compared sets of potentially pathogenicity-associated proteins, such as secreted proteases and enzymes involved in secondary metabolite production, with those of closely related onygenales (Coccidioides species) and the mould Aspergillus fumigatus. The comparisons revealed expansion of several gene families in dermatophytes and disclosed the peculiarities of the dermatophyte secondary metabolite gene sets. Secretion of proteases and other hydrolytic enzymes by A. benhamiae was proven experimentally by a global secretome analysis during keratin degradation. Molecular insights into the interaction of A. benhamiae with human keratinocytes were obtained for the first time by global transcriptome profiling. Given that A. benhamiae is able to undergo mating, a detailed comparison of the genomes further unraveled the genetic basis of sexual reproduction in this species.

CONCLUSIONS

Our results enlighten the genetic basis of fundamental and putatively virulence-related traits of dermatophytes, advancing future research on these medically important pathogens.

Differential gene expression in the pathogenic dermatophyte Arthroderma benhamiae in vitro versus during infection

Although dermatophytes are the most common agents of superficial mycoses in humans and animals, the molecular basis of the pathogenicity of these fungi is largely unknown. In vitro digestion of keratin by dermatophytes is associated with the secretion of multiple proteases, which are assumed to be responsible for their particular specialization to colonize and degrade keratinized host structures during infection. To investigate the role of individual secreted proteases in dermatophytosis, a guinea pig infection model was established for the zoophilic dermatophyte Arthroderma benhamiae, which causes highly inflammatory cutaneous infections in humans and rodents. By use of a cDNA microarray covering approximately 20-25 % of the A. benhamiae genome and containing sequences of at least 23 protease genes, we revealed a distinct in vivo protease gene expression profile in the fungal cells, which was surprisingly different from the pattern elicited during in vitro growth on keratin. Instead of the major in vitro -expressed proteases, others were activated specifically during infection. These enzymes are therefore suggested to fulfil important functions that are not exclusively associated with the degradation of keratin. Most notably, the gene encoding the serine protease subtilisin 6, which is a known major allergen in the related dermatophyte Trichophyton rubrum and putatively linked to host inflammation, was found to be the most strongly upregulated gene during infection. In addition, our approach identified other candidate pathogenicity-related factors in A. benhamiae, such as genes encoding key enzymes of the glyoxylate cycle and an opsin-related protein. Our work provides what we believe to be the first broad-scale gene expression profile in human pathogenic dermatophytes during infection, and points to putative virulence-associated mechanisms that make these micro-organisms the most successful aetiological agents of superficial mycoses.

Signature polymorphisms in the internal transcribed spacer region relevant for the differentiation of zoophilic and anthropophilic strains of Trichophyton interdigitale and other species of T. mentagrophytes sensu lato

BACKGROUND

Dermatophytes are the main cause of superficial mycoses in humans and animals. Molecular research has given useful insights into the phylogeny and taxonomy of the dermatophytes to overcome the difficulties with conventional diagnostics.

OBJECTIVES

The Trichophyton mentagrophytes complex consists of anthropophilic as well as zoophilic species. Although several molecular markers have been developed for the differentiation of strains belonging to T. mentagrophytes sensu lato, correct identification still remains problematic, especially concerning the delineation of anthropophilic and zoophilic strains of T. interdigitale. This differentiation is not academic but is essential for selection of the correct antimycotic therapy to treat infected patients.

METHODS

One hundred and thirty isolates identified by morphological characteristics as T. mentagrophytes sensu lato were investigated using restriction fragment length polymorphism (RFLP) and sequence analysis of the polymerase chain reaction-amplified internal transcribed spacer (ITS) region of the rDNA.

RESULTS

Species of this complex produced individual RFLP patterns obtained by the restriction enzyme MvaI. Subsequent sequence analysis of the ITS1, 5.8S and ITS2 region of all strains, but of T. interdigitale in particular, revealed single unique polymorphisms in anthropophilic and zoophilic strains.

CONCLUSIONS

Signature polymorphisms were observed to be useful for the differentiation of these strains and epidemiological data showed a host specificity among zoophilic strains of T. interdigitale/Arthroderma vanbreuseghemii compared with A. benhamiae as well as characteristic clinical pictures in humans when caused by zoophilic or anthropophilic strains. The delineation is relevant because it helps in determining the correct treatment and provides clues regarding the source of the infection.

Pets as the main source of two zoonotic species of the Trichophyton mentagrophytes complex in Switzerland, Arthroderma vanbreuseghemii and Arthroderma benhamiae

In cases of highly inflammatory dermatophytosis in humans, it is important to identify the possible source of animal transmission in order to prevent recurrence, family outbreaks or rapidly progressing epidemics. A survey of dermatophytes in pets during a 14-month period in Switzerland revealed, in addition to Microsporum canis, two different species of the Trichophyton mentagrophytes complex, Arthroderma benhamiae and Arthroderma vanbreuseghemii, all causing inflammatory dermatophytoses. Arthroderma benhamiae was only and frequently isolated from guinea pigs. Arthroderma vanbreuseghemii was isolated mainly from European short hair cats, but also from dogs and in one case from a pure-bred cat. Ninety-three percent of the cats carrying A. vanbreuseghemii were hunters and all had skin lesions. In contrast, cats with skin lesions that were strictly indoors were found to be almost exclusively infected by M. canis. Therefore, it can be suspected that infection with A. vanbreuseghemii occurred during hunting and that the natural source of this dermatophyte is either soil or an animal other than the cat, most probably a rodent.

Phylogenetic analysis of Trichophyton mentagrophytes human and animal isolates based on MnSOD and ITS sequence comparison

Dermatophytes are keratinophilic fungi able to infect keratinized tissues of human or animal origin. Among them, Trichophyton mentagrophytes is known to be a species complex composed of several species or variants, which occur in both human and animals. Since the T. mentagrophytes complex includes both anthropophilic and zoophilic pathogens, accurate molecular identification is a critical issue for comprehensive understanding of the clinical and epidemiological implications of the genetic heterogeneity of this complex. Here, 41 T. mentagrophytes isolates from either human patients (14 isolates) or animals (27 isolates) with dermatophytosis were prospectively isolated by culture and identified on morphological bases at the University Hospital Centres of Lille and Poitiers, and the Veterinary School of Alfort, respectively. The isolates were differentiated by DNA sequencing of the variable internal transcribed spacer (ITS) regions flanking the 5.8S rDNA, and of the housekeeping gene encoding the manganese-containing superoxide dismutase (MnSOD), an enzyme which is involved in defence against oxidative stress and has previously provided interesting insight into both fungal taxonomy and phylogeny. ITS1-ITS2 regions and MnSOD sequences successfully differentiate between members of the T. mentagrophytes complex and the related species Trichophyton rubrum. Whatever the phylogenetic marker used, members of this complex were classified into two major clades exhibiting a similar topology, with a higher variability when the ITS marker was used. Relationships between ITS/MnSOD sequences and host origin, clinical pattern and phenotypic characteristics (macroscopic and microscopic morphologies) were analysed.